Calculate bump steer toe change from tie rod geometry, steering arm length, and suspension travel.
Input Parameters
Results
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Toe Change
°
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Toe Change
mm
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Bump Steer Rate
°/in
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Tie Rod Arc Height
in
Note: Bump steer causes unwanted toe change during suspension travel. Minimized when the tie rod and control arm arcs are coincident. Excessive bump steer causes darting over bumps.
Reference
Arc Height = Tie Rod L x (1 - cos(arcsin(Bump / L)))
Toe Change = arctan(Arc Height / Steering Arm)
Bump Steer Rate = Toe Change / Bump Travel
Minimize by matching tie rod arc to control arm arc
Ideal: < 0.01° per inch of travel